Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Define water balance - hormonal control of fluid balance, Define Regulation...

Define Regulation of Water Balance - Hormonal Control of Fluid Balance? Hormonal control of fluid balance: When water intake is insufficient or water loss is excessive, the kid

Explain phylum ciliophora, Phylum Ciliophora 1) They have cilia at some...

Phylum Ciliophora 1) They have cilia at some stage in the life-cycle. The cilia are used for locomotion or creating a feeding current. 2) They feed heterotrophically usually

Ecological pyramids, What are the advantages of ecological pyramids?

What are the advantages of ecological pyramids?

Explain the determination of hydrolysis, Explain the Determination of Hydro...

Explain the Determination of Hydrolysis Hydrolysis of calcium pantothenate in acidic medium produces  α,γ-dihydroxy-β,β-dimethylbutyrolactone, which reacts with hydroxylamine i

In hormonal terms why does menses occur, In hormonal terms why does menses ...

In hormonal terms why does menses occur? Menses is the endometrial monthly desquamation that happens as the estrogen and progesterone levels fall after the regression of the co

Person''s red blood cell content of 2, How would carbon monoxide poisoning ...

How would carbon monoxide poisoning affect a person's coloring, particularly of the mucous membranes? How would it affect the hemoglobin concentration, hematocrit, and percent oxyh

What is the enzyme reverse transcriptase present in hiv, Q. Which type of v...

Q. Which type of virus is the HIV? What is the enzyme reverse transcriptase present in HIV? HIV is a retrovirus that is RNA viral (its genetic material is RNA and not DNA).

Difference between eye and camera, Difference between Eye and Camera - ...

Difference between Eye and Camera -   Camera   Ey e 1. Box.   2. Black inner paint   3. Shutter   4. Diaph

Exchange in alveoli, Exchange in Alveoli The blood that enters the lun...

Exchange in Alveoli The blood that enters the lungs from the heart has been routed through body tissue where mitochondria1 respiration has depleted its oxygen content. It thus

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd